Rice – Gas Grill vs. Burner for Paella

If you're putting your wood chips directly on a fire, it's good to soak them (and that means real soaking--a few days--not an hour or two). This prevents the wood chips from actually catching fire, which can cause off flavors from combustion chemicals settling back on your food. Tastes kinda like a brand new telephone pole smells on a hot day. Tar/Creosote, and not a nice flavor.

But on a gas grill, if you've got your chips in a pan or wrapped in a fairly tight foil pouch, you needn't worry so much about the chips actually catching on fire. As long as they just smoulder, you're good to go.

Whether or not charcoal tastes different/better is actually a bit of a debate. I've been a propane griller for years and now I use charcoal not for the taste, but because frankly, I like to play with fire. But lets assume that there is a taste difference, identify where the differences comes from, and how to address them:

1. The smoke from charcoal. This is (if you've been using natural lump charcoal) pretty much just wood smoke. If you've been using briquettes you'll also get the smoke of the filler and such, but generally this isn't desirable and we don't want to replicate it. For smoke on a gas grill - you can use something like this smoker box. Fill it with wood chips and place it over a burner, it should start smoking.

2. Vapor from the food drippings hitting the coals, and rising back up to flavor the food. This used to be a big advantage to charcoal, but its largely minimized by new gas grills with 'vapor bars'. As long as your grill has one of these, you're in luck. Otherwise, there's not a good, safe way to replicate it - but odds are you have it. Its a long bar usually running the length of burners.

3. Lighter fluid taste. Another undesirable flavor if you're doing a particular (and not good IMO) kind of charcoal grilling. Frankly, its not one you're likely to miss.

Those are the main tastes and how to replicate them. Nowadays the biggest is definitely #1, but it only matters if you doing foods that cook for a significant length of time or are especially 'porous'. If you're doing hot dogs and chicken breasts, I wouldn't bother if smoke. If you're doing burgers - maybe/probably. If you're doing thick steaks, thick pork chops, a whole chicken, or anything that's going on awhile, then creating some smoke is definitely worth it. ("Liquid smoke" definitely doesn't taste like the real thing.)